Press for embossing



sePt- 2, 1930- G". w. ALLlsoN 1.774,629

Jaro/wej:

' Sept. 2, 1930. G. w. LusoN 1.774.629

PRESS Fon lnossma Filed Jan. 16. 1929 2 shouts-Shut 'v 2 I I v I ;2057; ymm

Patented Sept. 2, 1930 PATENT OFFICE GEORGE WILLIAIVI ALLISON, OF LONDON, ENGLAINID PRESS FOR EMBOSSING Applicationv filed January 1G, 1929, Serial No. 332,854, and in Great Britain January 19, 1928.

My invention relates to an improved press for embossing in which the pressure is exerted by means of a pressure fluid which acts to force the material to be embossed into a 5 mould so that it will be moulded to the desired Shape. The operation of the fluid pressure is such as to ensure that the material will be forced into intimate contact with the Inould so as to fill in all the crevices and thus ensure a correct reproduction of fine detail.

It also enables a very considerable amount of relief to be obtained on the embossed material.

According to my invention an embossing press consists of two bodies or frames between which the intaglio or the like and the material to be embossed are adapted to be arranged, one of said bodies or frames carrying a resilient flexible surface forming an expansible wall of one of said bodies or frames connected to a source of `fluid pressure, means being provided to hold the bodies or frames in selected spaced relationship, and a control valve or cock for regulating the admission of pressure fluid for expanding the said flexible surface against the material to be embossed.

In carrying the invention into practice according to the preferred form a platen is employed adapted to be engaged over the material located against a mould and provided with means to form afluid tightjoint all round the platen. Fluid pressure is introduced between the platen and the material in the m'ould so as to exert the desired pressure thereon. The platen is mounted over a suitable bed in any convenient manner and simple means are provided by which it may be moved toward or away from the bed for the purpose of introducing the material to be embossed between each operation.

The platen can be in the form of a suitable rigid plate or frame over the undersurface of which is secured a sheet of resilient or fiexible material such as india rubber. A suitable frame engages over the edges of this sheet and means are provided to secure the frame to the upper plate of the platen so as to clamp the flexible Sheet between them. A 50 suitable inlet and outlet valve is provided by means of which pressure may be introduced between the platen and the fieXible sheet so that the latter will be expanded and pressed against the material to be embossed. The Outlet valve is provided to permit the pressure to be released after the embossing is completed. The inlet and outlet valve may be interconnected so that one will be opened as the other is closed and vice versa. As an alternative a single two-way valve may be employed which in one position will close the Outlet and open a way for the admission of fiuid to the space between the platen and the fiexible sheet and in the other position will cut ofi the supply of pressure fiuid and 55 connect the space to the atmosphere so as to allow the pressure fiuid therein to escape. A suitable pressure fluid for most purposes comprises air compressed to the desired pressure. This may be admitted to the space between the platen and the fiexible sheet and after the prescribed period may be exhausted to the atmosphere.

In order to comply with the requirements of high fluid pressure the frames have to be fairly heavy and consequently it is desirable to provide means for raising the upper frame other than manually. For this purpose the press can be supported upon suitable pistons and cylinders adapted to operate by pneumatic pressure so as to raise the platen to the desired height to enable the embossed article to be removed and a fresh one placed in position. Upon releasing the pressure, the platen will then descend of its own weight and may be secured in position by suitable clamping means.

The platen is preferably mounted to slide upon suitable upright guiding members and two or more pneumatic` cylinders are arranged upon opposite sides of the press so that the platen may be supported upon rods connected to pistons in the cylinders. Suitable valves are provided to admit air or other pressure fluid to the cylinders for the purpose of forcing:` up the pistons and thus raising the platen. These valves are preferably interconnected with the valves which control the admission and exhaust of the pressure fluid to the press for the purpose of elfecting the actual embossing operation.

n order that my invention may be clearly understood and readily carried into effect, I have appended hereto two sheets of drawings illustratingr an en'ibodiment of same7 and wherein Fig. 1 is a front elevation showing the press in a position ready for the embossing operation.

Fig. 2 is a plan view of Fig. 1.

Fig. 3 is a detail end elevation view of the upper part of the press.

Fig. t is a. sectional elevation of the fluid pressure chamber and expansible flexible surface.

Figi 5 is a front elevation view of the control valve-base for the fluid pressure supply, and

Fig. (i is a sectional side elevation on the line 7-7 of Fig. 7 of the control valve in the position for charg'ing the fluid pressure chamber for expanding` the embossing surface.

Fig. 7 is a` front elevation of the interior of the valve body and showing the position of the various ports when the embossing` surface is inflated.

Fig'. 8 shows the position of the ports when the elevating' cylinders are charged and the embossing` surface is defiated.

lieferring` to the drawinfa's the apparatus is shown by way of example as mounted upon a girder section frame in the form of uprights 1 with appropriate feet whereby the apparatus may be, securely bolted in position and horizontal frame members 2 supporting a stationary metal plate 8 adapted to support the intaglio or other embossing member upon which the material to be embossed is laid.

The desired embossing is obtained by compresscd fluid, preferably compressed air, and 'the action of the compressed air is distributed into the required embossing recesses by confining' the compressed air by a resilient flexible surface, preferably in the form of a rubber sheet, indicated by the reference numeral 4 stretched across the base of a heavy platen 5.

The arrangement of the resilient flexible sheet 4 is shown more clearly in Figi: L1 in which the edges of the sheet are shown securely ,Q'ripped between a rigid frame 6 and the plate 5. bolts 7 detachably holding the frame tight against the sheet 4.

It is preferred to have the lower face of the platen 5 a flat plane with the flexible sheet 4 normally :fiush against it. By this means an initial flat surface pressure can be obtained on the material to be embossed, and the sheet t together with the said piece of material subsequently forced by compressed air into the crevices in the intaglio or its equivalent.

The pressure fluid can be admitted to the inner side of the sheet 4 via a. central Vertical passage 8 in the platen 5, the upper end of the passage being provided with a suitable boss 9 to receive an appropriate T piece or other suitable coupling' 10 connccting a pressure fluid supply pipe 11 to the passage The pipe 11 is connected to a main pressure fluid supply conduit 13 via a control valve 1:2, the details of which are more clearly shown in Figs. 5 to 8 inclusive.

The control 'alve l'zl preferably serves as the main controlling device :for cll'ccting' the various Operations demanded for the production of the finished piece of material such as the raising'. lonerine' and looking' of the platen 5. If desired the platen 5 can be raised manually but this is undesirable as owing to the very high fluid pressure employed in an embossing' operation the parts have to be of very heavy metal. The platcn 5 can be raised by admittinr the pressure fluid to a pair of pistons 14- accommodating pisl'ons connected by rods 1 to the ends of the laten 5. the admission of pressure fluid beingY eii'ected by the operation of the valve l. this valve operation preferably beingT continuous with the operation to cut olli' the sul'iply to and relieve the pressure of fluid in the space between the sheet ll: and the platen 5. Pressure fluid pipes 1G connect the valve 12 to the cylindcrs 14;. The preferred form of valve 12 (see 5 to 8) consists of a fixed body part (1 over which is bolted a hollow ('ap 7) Oil having' a central boss c, which ma;v be provided with suitable packinr` in which rotates a valve spindle (Z ad apted to be rotated by any suitable handle. The valve spindlc (Z carries a disc c which seats tightly against the inner face of the body a, and for this purpose may be suitably spring` loaded. A clearance is provided round the sides and baclc of the disc c for compressed fluid which is a dniitted from the conduit 13 through an opening 13" into the cap Z).

The conduit 11 to the platen 5 is connected to a passage 11a in the body a of the valve, and the pressure fluid pas s through a port f/ in the disc c into the passaz'e ll". lVben il is desired to raise the platen 5 subsequent to an embossinr action the disc c is turned to bring' the port g' into regisl er with a pass-'age 16*nt communicating with the pipes lo.

An exhaust port 71, in the body (I, of the valve enables the pressure of iiuid in the cylinders 141 to be released when the platen :3 is connected to the source of fluid rn'essure.V and a further like port ;L1 enables the pressure fluid to be exhausted from the platen when the cylinders 14.- are being' charlg'ed. To enable the ports 71.v and /21 to be opened at the appropriate moments` an arcuate exhaust pass-:age 'i is provided in the disc rz which when tlu` port f/ registers with the passae'e llfL establishes coi'mnunication between the passaja'e 1Ga of the cylinder pressure fluid conduit and the eXhaust port h, and When the port g registers with the passage 16n the arcuaie exhaustpassage ('onnects the passage 11a with the exhaust passage hl.

lt is desirable when about to connect the platen 5 to the fluid pressure supply to ensure that the platen 5 is securely held against up- Ward movement, and is also released for upward movement when the cylinders 14 are about to be connected to the fluid pressure supply. For this purpose the operation of the valve 12 can be utilized to lock and release the platen. One way of eifec'ting this is by connectingV to the ends of the platen depending links 17, preferably four shown, each pair of links beingr connected by a transverse bar 18 which can conveniently be prolonged at one end to provide a handle 19. lVhen the platen 5 is lowered to the embossing position the links 17 are engaged by apertures 17a over the ends of fixed projectiiui` bars 20 secured to the frame 2. The links 17 are lowered to this position by the rotation of a disc 21 secured to the valve spindle (Z.

The disc 21 carries a pair of symmetrical raised cam surfaces 22 and 22a, one on each side of the disc. The cam 22 is adapted to engage the inner end of an arm 23 pivotally connected to the handle 19 of one pair of end links 17 and the cam 22a has a similar action on the inner end of an arm 23 connected likewise to the other pair of links 17. The arrangement of the cams 22 and 22a is such that when the valve 12 is operated to connect the platen 5 to the source of fluid pressure the links 17 can fall on to the projections 20, and when the valve 12 is being" set to charge the cylinders 14 the cams 22 and 22a engage the inner ends of the rods 23 and 23a and push them outwards thereby releasing the links 17 from the projection 20.

A handle 211 can be provided. on the disc 21.

The escape of pressure fluid from the passage 8 can be accelerated by opening an auxiliary valve 8a.

I claim 1. An embossing machine comprising a frame, a base plate having an upper press surface, a platen supported above said surface, a flexible sheet secured across the undersurface of said platen and sealed thereto around its edges, means for causing` movement of said platen towards said plate, a source of fiuid pressure in communication With said sheet and said means, a valve for controlling supply of fluid pressure to said sheet and to said means, members carried by the platen, abutments adapted to be engaged by said members, and a rotary member operated simultaneously with the operation of the valve and adapted to impart movement to said members, the arrangement being such that when the valve is operated to supply fiuid pressure to said sheet the said members engage the abutments and lock the platen in position, and. when the valve is operated to exhaust the pressure from the sheet the members are moved to release the platen.

2. An embossing` machine comprising a frame, a base plate having an upper press surface, a platen supported above said surface, a lexible sheet secured across the undersurface of said platen and sealed thereto around its cdges, means for causing,` movement of said platen towards said plate, a source of fluid pressure in communication with said sheet and said means, a valve for controlling supply of fluid pressure to said sheet and to said means, link members carried by the platen, fixed abutments adapted to be engaged by said members, a rotary member operated simultaneously with the operation of the valve, a pair of cam projections on said rotary member, arms connected to the link members and engaging said cam projections, the cam projections being` adapted to force said arms outwards during,` rotation of the valve to release the links from said abutments when the valve is set to out off the supply of fluid pressure to said sheet, and to permit said link members to engage the abutments When the valve is set to connect the platen to the source of fluid pressure.

8. In an embossing machine a main frame, a base plate having an upper press surface, a pressure head supported above said plate, a flexible sheet secured across the base of said pressure head, a pressure fluid connection between said pressure head and a source of supply for expanding said fleXible sheet pressure fluid operated means for bringing the pressure head and the base plate towards each other, a valve controlling` the admission of pressure fiuid to said pressure head and said fluid pressure operated means, locking members for preventing movement of the pressure head when pressure fluid is being` admitted to it, a connection between said valve and said looking members whereby when the valve is moved to cut off pressure fluid supply to said pressure head the pressure head is released for separation from the said base plate by the operation of said fluid pressure operated means.

L1. An embossing` machine comprising a main frame, a base plate having an upper press surface, a pressure head supported above said plate, a fieirible sheet secured across the base of said pressure head, a pressure fluid connection between said pressure head rmd a source of supply for eimanding said flexible sheet pressure fluid operated means for bringing the pressure head and the base plate towards each other, a valve controlling the admission of pressure fiuid to said pressure head and said fluid pressure operated means, a rotary member for operating` said valve, looking members moved in unison with said rotary member, abutments carried by said pressure head adapted to be engeged by said looking members, ports With said valve reguiating the supply of pressure fluid to said fluid pressure operated means Wherehy mie position of said Valve eifects eperatiou of the pressure fluid operated means to bring the pressure head and base plate together :md another position of said valve udmts vfluid pressure to said pressure head, the arrzuigement being that when said valve if: nmved to release the fiuid pressure iu said pressure head the said looking members are nim'ed away form said abutments.

GEORGE VILLIAM ALLISON. 

